We have formulated the quantative diagnostic index to measure the malignancy of oral cancers based on the results of analyses of cancer cell kinetics. The analyses involved the histological as well as inaunohistological study of intranuclear proliferation-associated factors such as Ag-NORs, BrdU, proliferating cell nuclear antigen(PCNA)and the oulticytofluorometry of nuclear DNA as well as RNA quantities and the multivariate analysis of these results vis-a -vis clinical and pathological factors.1. Cell KInetics in Oral Cancers : The quantitative variations in nuclear DNA and RNA have been observed to reflect differnces in cell kinetics in oral cancer cells. The relationship between the changes nuclear DNA-RNA cytogran and cell image condition in the course of treatment through external radiation and/or the administration of PEP or CDDP revealed that the number of cells containing high DNA and RNA quantity levels increases in proportion to the effectiveness of the treatment given(G2N-ph
… Morease block)from early stage of treatment and this is accompanied by a similar increase of denatured cells. On the other hand, when the effectiveness is low, little change occures in the nuclear DNA as well as RNA quantities and the cell image condition. From these results, it has been confirmed that cytogram observation results can be used to find treatment effectiveness, and the susceptibility. There is a positive relationship between the number of intranucleous Ag-NORs and cellular proliferation activity, and from this, the decrease of the number is considered to represent a decline in the activity or a process leading to necrocytosis. The number of PCNA labelling cells corresponds to the changes of BrdU labelling cell number, and it has been confirmed that this phenomenon can be used effectively to detect S-phase cells.2. Cell Kinetics in the Epithelial Cells around Oral Cancer : In the raucous membrane around buccal pouch cancer that was induced by administering DMBA to a hamster, epithelial dysplasia and papillary hyperplasia in various developmental stages were observed. The nuclear DNA quantity variants and the frequency of the appearance of cells over tetraploids in these abnormal tissues resembled the conditions in cancer. In the clinical cases of epithelial abnomalities around oral cancer, too, an aneuploidy pattern has been observed in nuclear DNA quantity(change). And there have been many cases in which the nuclear DNA variants and the appearance frequency of the cells over tetraploids exceed the minimum levels of oral cancers. Consequently, it has been found that there is a high possibility for these epithelial tissues turning into a malignant tumor.3. Multivariate analyses have found that lyaph node metastasis of oral cancer is affected by the size of primary lesion, its location, ocular inspection findings, degree of histological malignancy and nuclear DNA-RNA cytogram pattern, and effectiveness of radiation therapy or chemotherapy is affected by nuclear DNA as well as RNA quantities and cell proliferation-related factors. Less